Things have changed since we last wrote about ACROS. When the building, which was designed by Emilio Ambasz & Associates, was first built, many of the trees that make up its “step garden" were still saplings. Now, many of the plants are so tall that they obscure the stair railings, which were clearly visible just a few years ago. In fact, you have to crane your neck to see over the trees as you ascend the leafy levels, and at times you feel as though you’re basically standing in the middle of a miniature forest.